New York City’s Noguchi Museum said on Wednesday it fired three employees after they violated its updated dress code by wearing keffiyeh head scarves, which have become an emblem of solidarity with the Palestinian cause.

Across the world in protests demanding an end to Israel’s war in Gaza, demonstrators have worn the black-and-white keffiyeh head scarf, saying it identifies with Palestinian self-determination. Israel’s supporters say it is provocative and a sign of backing extremism.

Israel’s ongoing military assault on Gaza, which has killed tens of thousands and caused a humanitarian crisis, followed a deadly attack by Palestinian Hamas militants on Oct. 7.

Last month, the art museum — founded by Japanese American sculptor Isamu Noguchi — announced a policy prohibiting employees from wearing anything that expressed “political messages, slogans or symbols.”

“While we understand that the intention behind wearing this garment was to express personal views, we recognize that such expressions can unintentionally alienate segments of our diverse visitorship,” it said in a statement.

Natalie Cappellini, one of the three gallery attendants who was fired, took to Instagram to say the museum leadership was weaponizing the term “political” against the Palestinian cause.

Reuters was unable to reach the other two fired employees.

The keffiyeh has long been a symbol of Palestinian nationalism, exemplified by the late PLO leader Yasser Arafat, who was rarely photographed without one.

In November, three students of Palestinian descent in Vermont were shot in an attack under investigation. Two of them were wearing the keffiyeh.

There are previous instances in the United States of people losing jobs due to their stance on the Israel-Gaza war.

A New York City hospital fired a Palestinian American nurse in May after she called Israel’s actions in Gaza a “genocide” during an acceptance speech for an award. Israel denies genocide charges brought by South Africa at the World Court.